Quick Answer
AQL (Acceptable Quality Limit) is a statistical sampling standard that defines how many defects in a sample are acceptable before a shipment is rejected. Most buyers use AQL 2.5 for major defects and 4.0 for minor defects, with zero tolerance (AQL 0) for critical safety defects.
How AQL Levels Work
| AQL level | Typical use | Tolerance |
|---|---|---|
| AQL 0 | Critical / safety defects | Zero accepted |
| AQL 1.0 | Medical, precision products | Very strict (1%) |
| AQL 2.5 | Major defects (most goods) | Standard (2.5%) |
| AQL 4.0 | Minor / cosmetic defects | Relaxed (4%) |
| AQL 6.5 | Packing / labelling checks | Lenient (6.5%) |
Sample size is set by the total order quantity and inspection level (usually General Level II). The inspector samples that many units and applies the accept/reject numbers for your AQL.
Key Takeaways
- AQL defines acceptable defect rates for a sample.
- 2.5 (major) / 4.0 (minor) are the common standard.
- Critical safety defects use zero tolerance.
- Sample size depends on order quantity and level.
Frequently Asked Questions
What does AQL mean?
AQL stands for Acceptable Quality Limit — a statistical sampling standard that sets the maximum number of defects in a sample before a shipment is rejected, classified by defect severity.
What AQL level should I use?
Most buyers use AQL 2.5 for major defects and 4.0 for minor defects, with zero tolerance for critical safety defects. Medical and precision products often use stricter levels like 1.0.
How is the sample size determined?
By the total order quantity and the inspection level (usually General Inspection Level II). Standard AQL tables convert these into a sample size and accept/reject numbers.
What is the difference between critical, major, and minor defects?
Critical defects are safety or regulatory failures (zero tolerance); major defects affect function or saleability; minor defects are small cosmetic issues. Each has its own AQL threshold.
Can Plutonia inspect using AQL standards?
Yes. Plutonia applies AQL sampling (typically 2.5/4.0, stricter for regulated goods) against your checklist and reports the result clearly. Submit your order details to start.